BB removal after loctite has been used

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toastie
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by toastie

I have just purchased a used addict SL with campag super record and want to change the crank out for my power meter but it appears the cups have been glued in to the frame, any tips on getting them out without causing damage?

alcatraz
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by alcatraz

Even with loctite 609 which is pretty strong stuff the process is to knock the cup/bearing (or whatever is pressed) out with a good blow.

Is it free of risk, no.

Can heat be used? Most of the time no because the loctite retaining compounds like 609 have a melt temperature of 150C which would possibly damage the carbon.

If I had some time I'd probably try devise a press that could press the cup out. Be it with a cup removal tool or not. Pressing is better than hitting.

I see no reason to put the strong retaining compunds on cups. They are meant for bearings I believe. So if the mechanic wasn't an idiot you have something that appears solid but just needs a good impact to break loose.

You skills as a mechanic are going to have to decide when the impact strategy becomes a risk to damage the frame.

Are you just after swapping bearings or bb standard? Maybe you can swap bearings without removong the cups. They will guaranteed be creakless :D

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toastie
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by toastie

im swapping BB standard, i have tried my parktool removal tool and a drift with as much force as im happy to use but with no visable effect to either cup, i was hoping there would be some "chemical" that could be used to help soften it

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Calnago
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by Calnago

Is the install using Campy cups? Are you using a Park Headset removal tool? Which one? I’ve actually intentionally bent the prongs on one of those to perfectly fit some Campy cups.
Make sure the prongs are squarely and firmly against the ridge of the cups. Do not do this in a stand. Brace the bike somehow. One good blow is all it should take. Mamby pamby taps will do nothing.
If retaining compound has been used with a Carbon fiber shell, it’s my opinion that a strong forceful impact is much better than a slow removal tool. Reason... the bond first needs to be broken. Slowly pulling at it will tend to want to pull fibers with it as well. If a retaining compound has not been used, then a puller/pusher of some sort would be fine. But if you need to break the bond do it quick and dirty. There’s no absolute guarantee that some fibers wont get damaged, but I’ve never damaged one yet, aside from the inherent micro stuff that will happen simply as a result of pressfit cups being removed and installed, regardless of whether any retaining compound has been used.
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hambini
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by hambini

I would heat the bottom bracket area so it's warm but not red hot. That will make it easier for the bond to break.

I disagree with Calnago, I would go for a slow removal rather than a short blow. Carbon Fibre is brittle. Heavy blows can cause micro cracking.
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kode54
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by kode54

since you bought it used...are you sure they are press fit and not threaded?
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Calnago
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by Calnago

The blow is not to any carbon surface directly, it is directly to the cup and just to break the bond of the retaining compound. A little heat is fine prior to this so long as it’s not so much as to soften the resins in the carbon, or wreck the paint, but I think Loctite says a temp of 250 degrees Centigrade is what’s required to break the bond which would not be very safe for your frame or paint.
Out of curiosity, what tool would you recommend to remove a Campy Pressfit Ultratorque cup slowly that has been installed with retaining compound and that wouldn’t damage the external BB area paint in the process? The thing is, even if it is a slow removal the bond still needs to be broken so the force would have to slowly build up to enough force to initially break the bond. Build up, build up, build up (all the while slowly wanting to, and maybe succeeding at, pulling some carbon fibers with it)... then pop!... the bond breaks. It’s not like the force is a nice even pull from beginning to end as it would be if there was no retaining compound involved. I’m good with the quick and painless method, but to each his own. Some residual retaining compound on the shell can then be removed carefully with an Exacto knife or something. It’s pretty easy.
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mrfish
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by mrfish

No heat. Ignore the advice to heat to warm but not red hot. Firstly if the cup gets hot it will expand with obvious results. Secondly frames are designed to withstand a hot day in a car, not 200 der C so the designer would not have spent money on a heat resistant epoxy system. Third, heat guns tend to burn edges and smaller parts long before the main item heats up.

So your options are
1. bash it out as Calnago says.
2. slot it then peel it out like a seatpost. Not advised but theoretically possible.
2. Machine them out. Expensive and not commonly done. Not difficult for a trained machinist with the right tools, but will cost more than the frame if you pay for it as it takes time to do right.
3. Campagnolo crank with PM or PM pedals etc.

I would start by asking the seller to tell you how the cup is fixed in place. If retaining compound used, take it to a good bike mechanic. If epoxied ask for your money back.

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Calnago
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by Calnago

Agreed, if epoxy has been used, that’s a whole ‘nother thing. But really, a proper tool butted up against the edge of the cup accompanied by a good sharp blow should knock it out cleanly. At least I’ve never experienced anything otherwise. I have a heat gun but have never used it for this purpose. Really, it’s no different than removing the pressed in headsets that were used pretty much 100% not so long ago. Ask your bike shop how they do it. When I first started dealing with situations that required a retaining compound, I also was worried about removal down the road. Called around. Talked to Calfee as to what they do when someone sends them a frame for a repair and/or respray. The answers I got were universally the same... impact with a proper tool. And personally, I’ve never had a problem with it and any frame I’ve worked on like this has remained creak free. If the pressfit tolerances of the shell are good, I generally use Morgan Blue AquaProof Paste which is not a retaining compound but prevents corrosion. Or I’d be ok with a dry install. But never grease. If someone brings me a frame with a persistent creaking problem, that’s when I’ll use a retaining compound plus primer and be confident it won’t be moving.
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Gearjunkie
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by Gearjunkie

I used the recommended primer and loctite method for the BB in my Evo Nano Black (PF30A).

Year or two later decided to change from the plastic shell to a Hawk Racing BB (alloy shell).

Couldn't move the plastic shell with the Park Tool, no matter how hard I smacked it with a large hammer and with the frame well supported on the ground and even after removing the bearings from the shell.

Ended up slotting the plastic shell and then pulling it out in multiple parts with needle nosed pliers. It was so well fixed in that each small part of the plastic shell needed quite some work to remove it and then plenty of residue was left over.

Used water proof grease (rather than loctite) on the alloy Hawk Racing shell that replaced the original. Pressed in nicely and then never moved or creaked from then on. My take is that the PF30A alloy shell is much less likely to creak as well as being easier to install and remove at the cost of maybe 5g extra weight.

But that's just my experience, not at all a statistically significant sample size :thumbup:

GJ

Valbrona
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by Valbrona

alcatraz wrote:
Sun Jul 29, 2018 3:56 pm
If I had some time I'd probably try devise a press that could press the cup out. Be it with a cup removal tool or not. Pressing is better than hitting.
I think in the case of glued in cups short/sharp stuccato-style hits are mechanically better than big wallops or pressing out.

alcatraz
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by alcatraz

Does the bike have a carbon or an alloy shell? Is it an open shell or is it a pipe,tube going between the ends?

What material are the cups made from?

sungod
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by sungod

if it's loctite 609, probably the most commonly used for bb, you can weaken it by raising temperature...
at 100c it's lost 25% strength
at 130c about 50%
at 150c about 70%
at 175c it's finished, but this is probably getting a bit hot for some epoxy

if the frame has metal inserts and surfaces were cleaned and primed, 609 can be extremely hard to break, i'd fitted bb30 (steel on steel), even with the bb shell braced against a hard surface i couldn't shift the bearing with a hammer, i pounded on it so hard it was scary, using bolts+washers to try and pull it out simply buckled the thick steel washers, heated with a hairdryer they tapped out easily

if you can apply heat to the cups with a hair dryer (use foil to make 'shields' to keep hot air off the cf), i think you'll be able to tap them out without too much force(assuming it's 609 and not something crazy)

alcatraz
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by alcatraz

How fond are you of your paintwork? :D

The paint will go before the carbon does.

/a

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toastie
Posts: 70
Joined: Sun Dec 20, 2015 11:55 pm

by toastie

Frame is a addict SL hmx carbon. BB she’ll is open carbon and cups are alloy, I contacted previous owner who said he used loctite but couldn’t remember which one! Frame isn’t in a stand but is well supported and I started using the park tool headset tool with the prongs bent out and an aftershock hammer with hard sharp hits as I think this is the best way to break a bond rather that lots of little taps. I then tried an internal bearing puller connected to a slide hammer and it hasn’t budged at all. I think I will try and use a gentle heat followed by freeze spray directly to the alloy cup and see if this will “fracture” the bond, will also see if there is a loctite solvent that will soften the loctite

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